In today's ever expanding range of technologies, there are numerous applications for a manipulator to perform operations which normally would be provided by a human being, but these operations are to be carried out in an environment that may be detrimental to the individual. Typical of such environments is that associated with the nuclear industry. Within that industry there are numerous applications where radioactive material must be handled which would be normally harmful to the individual. Handling of this material ranges from taking samples of liquids, gases and solids, disassembly of components which have contained or been subjected to nuclear radiation of some form wherein a residual radiation level exists, or the operation of apparatus under conditions wherein potentially dangerous nuclear radiations exist. Such operations are normally carried out in units referred to as "hot cells" which are rooms of varying sizes surrounded by walls giving adequate protection to humans from the radiation involved. In order to carry out the various operations that are desired with these materials, numerous types of remote manipulators have been developed such that the operations which normally would be conducted by an individual may be performed using a "slave" portion of the manipulator as directed from a "master" portion. The operator, through the manipulation of the master, accomplishes the various operations using the slave portion. Usually the operator is provided with a viewing window and/or a closed circuit television system so that the interior of the cell can be observed during the particular operation.
Various types of manipulators have been developed in the course of the nuclear industry history. Some of these use completely mechanical systems wherein there is a direct mechanical connection between the master and the slave. These manipulators penetrate some type of opening in the cell wall with appropriate shielding preventing the escape of radiation into the area occupied by the operator. Other manipulator systems use an all electric system and still others utilize a mixture thereof. Typical of the manipulators that have been developed are those shown and described in U.S. Pat. Nos. 3,164,267 issued Jan. 5, 1965 to D. G. Jelatis, et al; 3,425,569 issued to L. W. Haaker on Feb. 4, 1969; 3,481,494 issued on Dec. 2, 1969, to H. Walischmiller; 3,923,166 issued to D. A. Kugath, et al. on Dec. 2, 1975; 4,298,300 issued to D. Francois; et al. on Nov. 3, 1981; 2,978,118 issued to R. C. Goertz, et al., on Apr. 4, 1961; 2,858,947 issued to H. G. Chapman, Jr. on Nov. 4, 1958; 4,370,091 issued to Gagliardi on Jan. 25, 1983; and 4,460,302 issued to C. Moreau on July 17, 1984. None of these devices, nor any combination thereof, is known that will meet the demands of the current remote manipulating art.
A review of the above-identified patents and other references describing various types of remote manipulators will reveal that these devices are complex in nature. They involve in some instances several motors, gears, and various types of drive trains, all of which are subject to failure of some type or other. It will be recognized that once any of these devices have been utilized in an environment where nuclear radiation is present, the devices themselves must be handled remotely if maintenance is to be performed. Furthermore, the presence of radiation is generally detrimental to lubrication and various physical characteristics of the materials employed in the manipulators which further produces various types of required maintenance or refurbishing. For any of the known manipulators the maintenance or refurbishing takes the manipulator out of operation for a substantial period of time since all of the manipulators must be decontaminated and taken to an additional cell for such action.
Not only is it desirable that a manipulator be able to perform the operation normally associated with a person, which includes all of the normal arm functions, but also it would be desirable to be able to extend the reach operations of the slave unit over and above those that are available to an operator at the master unit. This may be necessary because of the location of an object within the cell upon which work is to be performed. For example, the object may be well above the normal reach of a manipulator if the manipulator only follows the operations of an operator's arm. Except for some extensible capabilities (see U.S. Pat. No. 3,425,569), the other manipulators have very limited capabilities.
Accordingly, in view of the deficiencies of other master-slave manipulators, it is one object of the present invention to provide a manipulator wherein each arm or major components thereof of the slave portion may be readily removed and replaced as needed for maintenance and/or repair.
It is still another object of the invention to provide an all electric manipulator for use in hot cells and the like which will follow the basic movements of an operator but provide features to extend the use of the manipulator beyond the capabilities of the operator when necessary or desired.
It is another object to provide a manipulator which may be operated with the slave arms operable in either an "elbows up" or "elbows down" position to enhance the capabilities of the device.
It is also an object of the present invention to provide for interchangability of the arms of the slave portion, and components thereof, so as to minimize the inventory of components for manipulators.
It is a further object of the present invention to provide a manipulator that has self maintenance and repair capabilities whereby no additional manipulator is required for many types of such maintenance and repair.
It is an additional object of the present invention to provide an all electric manipulator wherein electrical coupling of interchangable components thereof occurs when the components are mechanically coupled.
Another object of the present invention is to provide a manipulator having a lift capacity to weight ratio of about 1:1.
Still another object of the present invention is to provide an improved boot member to encase joints thereof.
Further objects of the invention will become apparent upon a consideration of the drawings and the description as set hereinafter.